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    Select the number from among the given options that can replace the question mark (?) in the following series.11, 9, 15, 13, 19, ?
    Question

    Select the number from among the given options that can replace the question mark (?) in the following series.
    11, 9, 15, 13, 19, ?

    A.

    25

    B.

    17

    C.

    7

    D.

    21

    Correct option is B

    Given: 11, 9, 15, 13, 19, ?
    Logic: Each number is increasing by + 4 alternatively.
    First series: 11, 15, 19
    11 + 4 = 15
    15 + 4 = 19
    Second series: 9, 13,  ?
    9 + 4 = 13
    13 + 4 = 17
    ? = 17.
    So, missing number is : 17.
    Thus, the correct option is (b) 17.

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